The present invention relates to a new and distinct cultivar of Cornus kousa, or kousa dogwood that is grown for use as a landscape tree. It is known botanically as Cornus kousa and will be referred to hereinafter by the cultivar name ‘SUMMER GOLD’.
‘SUMMER GOLD’ arose and was selected by the inventor at the inventor's nursery in Molalla, Oreg., as a chance seedling in a field-grown crop of Cornus kousa (species, unpatented) in 2002.
The new Cornus variety ‘SUMMER GOLD’ is an upright tree characterized by variegated foliage. The leaves of ‘SUMMER GOLD’ are predominantly mid green in color and exhibit a prominent gold margin. The foliage variegation is maintained through the summer.
‘SUMMER GOLD’ may be compared with the species parent as follows: Whereas the species parent bears non-variegated green leaves, ‘SUMMER GOLD’ exhibits variegated foliage as described herein.
The closest known comparison varieties known to the breeder are the two variegated cultivars Cornus kousa ‘Okhan’ (unpatented) and the inventor's variety Cornus kousa ssp. chinensis ‘Tri-Splendor’ (U.S. Plant Pat. No. 20,008).
When compared with ‘Okhan’, ‘SUMMER GOLD’ bears wider and flatter leaves and is more vigorous in its growth and branching.
When compared with ‘Tri-Splendor’, ‘SUMMER GOLD’ produces more lateral branches and retains its variegation throughout the summer, whereas ‘Tri-Splendor’ becomes increasingly non-variegated as summer progresses.
‘SUMMER GOLD’ was first asexually propagated by the inventor in Molalla, Oreg. in 2005. Asexual propagation was accomplished by grafting ‘SUMMER GOLD’ onto seedling understock. Since that time, under careful observation, the distinguishing characteristics of ‘SUMMER GOLD’ have been determined stable and uniform, and are reproduced true to type in successive generations of asexual propagation.